Centrifugal pump.



No. 839,164. PATENTBD MAY 26, 1908. E. P. WELCH.

`GLNTRIFUGL PUMP.

APPLICATION FILED Amm. 1907. y

s .SHEETS-SHEET s.

#1271556 @s g K ,52067220773 the blades are extended rearward y with ref lation to the direction ofrotation, this action becomes partly posi-tive, ytli`a`. 1. is, a sort of f wedging action begins-to.'take'placd whichA action increases astiieblades appro-ach the -.t`angeiit. The 'more 'nearly-'theblades 'ap-f -proacli the tangent theggreater'isfthe extent unie ci water vwill be 4constantly. forced out- Centrifugal' Punips,. `ofwhich thefollowing 'lln's invention relates' to that c ass o centrifugalpumps'in'which ai 'series of rotary" f ln- .the ordinari action ofvv afeentrifug'al -and therefore,- other things "being equal,l the greater theforee .with which the' water may 'The ebject ofmy invention is .to produce a 'cent the 'periphery'aie so' arranged as .to ap;

-proach the tangentas closely as pra'cticablein order-that vthe water -inay 'be forced from the casing at as. hi ha, pressure as possible,

,STATES PATENT opinion.

EDWARD- F. wntca'or LAWRENCE, iiiA'ssAeHsnTirsjfl 1 CENTRIFUGAL- PUMP.

. ne. ssa-,164.- Y

To all whom it concer/n: v' 1 Be itvlinown that L'EDWARD F. WELCH, of Lawrence, county of Essex, State of Massaehusetts,'. have inventedv an Improvement in description, in connectionwith the accompanying drawings, is a specieation,like charactei's onthe drawings' representin like arts.

blades. o r' -ini'pe'lle'rsl are. provided within a casing, and the water isxforcedoutwardly asl they are rapidlyrotated.'-

pump-, if-"the' bla es .ofl the'impeller extend pump the water will be centrifual, but`,x.if

which they are enabled to .actin this manner .be ejected. Infpunipsfof this character the pumping actionA is {0f-ten much impeded by. thel action of the-water. inufalling back b e- :tween the blades, and -in' being vcarried around betweenthein practically .dead. l

i 1n order to vincrease th f. `pressure' with whicli'tlie water-'is ejected, it is customary t o' Ia1'ra'iige two or increpumps in tandem.

This".increased. attendantf expense is', .off

course, .-objectionable, but the lack of effi-' cien'cy in-'tliis-inethod is itsfchief ob] ection,

centrifugal pumpl in which the blades'adja-j and' in which backo vvv of water between'the blades will be prevented and th'ewloole vol#- wardly. For' an understanding of the' means which I einployin Vcarrying out "this ob3.ect, re er ence is: made to 'the' vaccompar'iyfing drawing, in which, Figure y,1' is a side eleyation-ot 'the' outer Spee'icatioxiof Letters Patent'. A 'l 4application. filed August 9, 1907; j Serial No. $817,756.

casing; of theft"centrifugal pnmp. rovided. with inyinvention; "Fig 2 'is a similar .yiew

Patented Mayecyieos.

on an enlarged scale the .casing removed. .'fFig. Sisacentral vertical and areiace views oilportions-,offthe iinpeller'. Figs. 6 and i7; .are

detail sectional views of the iinpellers. 1' .1.1. -f

'llie 'casing of the pump-comprises circular end walls a, a", and an involuteside wall a2,

the latter having tangential` discharge outlet ai? leading therefroin7 and. the-Wall a having -a a, o are provided with bearings eiland. a rej dished sojthat the convergeasthey approach the sidewal a?, so that theinclosedf cubical contents for each. fsectio'nj.v offradiusf will be approxinately the-saine. a The walls exactly radially, the -forcewhich acts. to-

'b er.. and apairyof shafts'bandf'c a'lfiespecd tively journaled therein-in axial alinement.

. An impellei' hubd is rigic'lly k mounted u on the inner end of the shaft band said hu is provided with a eircularfsile wall dpwhich.

`e itends. 4therefrom 'for' approximately. half the diameter'of the impeller.. fA..series of blades 4e extend froi'ntlie'hubd tothe edge of `wall d,. and are preferably cast integral with said-hub and said Wall. -p

An annul r wall formed ntegr'al with said blades e at .their opposite endsfi'oin wall pointbetween the edgeoflwalld and thehub 1to thewaterway between Athe irripelle'riand -'v the sided2 of the'casinggsaidwalls1d', d2,

'of. wall d2- tothe outer edge'ofwalldandare' formed integral at their ends with said-walls d', d2 respectively. 1- `An. impeller. hub g-l is {inounted on the shaitfc and is .provided Withl anintegral, circular, imperforate. .wall g,

'which extends the saine radial distance f roni the axes as the wall'd said-wall lying closely adjacent/the outer side' ofwall'd. series of blades h are'arranged with their inner' Vedges adjacent the miter'edges of.; blades e. and f, with their ends' integral withiwall -g and an annular wall g2, which is located close to the inner `side ofwall: dand extends thev nered'ges 'adjacent the outeredges of blades h, andwiththeir ends respectively integral los same radial distance as'f'saiddblades A series of blades t are arrangedfvviththeir inhich is located'adjacent the inner side of wall g. A series of blades 7c are arranged with their inner edges adjacent the cuter edges of blades 'i and with their ends respectively integral with the wall g and an annular wall g3 which is located close to the inner side of wall di, and 'extends to the outer edge thereof.

In operation the shafts b and c will be rotated in opposite directions, they being rotated respectively in the direction of the arrows, :c and y in Fig. 2. As best shown in Fig. 2, all of the blades have convex actingfaces and all of, them extend rearwardly, with relation to their direction of rotation, as they extend radially. The extent, however, which each successive set ofblades approach `the tangent, increases as they approach the periphery, so that the outer portions of the blades kextend nearly ina tangential direction. The outer edges of the blades of each set also extend approximately oppositie their inner edges, so that they practically overlap one another.

` The pump having been filled with water, when the shafts are rotated' as described, the water adjacent the hub d will becaught by the blades e and f and thrown outwardly by centrifugal action and also by the blades on l the convex sides thereof. As the water leaves the ends ofthe blades @and jf it will be picked up on'the convex sides of the blades h, which will, in turn, force the water outwardly, so that it is next picked up on the l convex sides of the blades' i, and these in turn force it outwardly until itis icked up on the convex sides of the blades l?, 'which force it into the surrounding chamber, from which it will be discharged through the tangential outlet.

As the outer end of each blade extends opposite the inner end of the next, the water is not only effectively prevented from iiowing backwardly, but is constantly impelled outwardly and, as the successive sets of blades increase in inclination to the radius from the center outward, the mechanical advantage of the blades on the water is correspondingly increased, so that the force with which the' water is ii'npelled as it approaches the casing is rapidly increased. may be stated that the action of the inner blades as compared to the action ofthe outer blades is similar to that'of a blunt Wedge to a sharp wedge. It will benoted that while the nearer-a set of blades is to the periphery, the nearer they approach the tangent, yet the corresponding increase in speedl due 'to their radial position-offsets the increase of the angle from the radius, so that the rapid-- ity with which the water is forced outward is not reduced. inasmuch as the outer blades 7c lie .nearly in the direction-of the n'tangent and move at a correspondinglyhigh velocity, the water may be forced out of the having an outer series of In' this connection itdischarge at the deshed pressure' without employing a series of pumps.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1.. A rotary pump comprising apair ofimpellers rotatable in opposite directions, one of said impellers having a double series of concentrically arranged blades and the other having a single series` of blades concentric f with said double series and disposed theretion to a radialposition, the blades of one series extending oppositely to the blades of the next adjacent series, and the extent of divergency from a radial position being successively increased from the axis outward, so that the outermost blades extendV nearly tangentially, substantially as described.

3. A rotary pump comprising a casing, a pair f oppositely rotatable shafts mounted in opposite ends of said casing in axial alinement, one vof said shafts having a radially extending support adjacent one end ofthe casing, said support having an intermediate vseries of blades mounted -thereon at one end and extending towardsthe opposite end of the casing, a support mounted on theother shaft and extending radially vtherefrom adjacent and within the rst named support andl having an inner series of blades mounted atone end thereon within said intermediate series, a support connected to the opposite ends of said inner blades at a distance from the supporting shaft thereof, extending radially adjacent the opposite ends of said intermediate blades from the sup ort thereof and ladesmounted thereon extending opposite said intermediate-series and the blades of one shaft being oppositely inclined to the blades lof the other shaft, substantially as described. l

4. A rotary pump comprising' a casing, a pair of oppositely rotatable shafts mounted in opposite ends iof said casing in axial alinement, one of'said shafts having a radially extending support adj acent one end of the casing, saidsupport having a double series of outer blades concentrically mounted thereon at one end and extending. towards the oppo site end of the casing, a support mounted on the other shaft and extending radially therefrom adjacent` and within the first named support and having an inner series oiblades mounted at one end thereon, a support conthe Yother end. of said inner blade-s,`

at aidiscanc. from the Supporting Shaft there* Lof, Midex-tending radially adjacent the opp' site ends of saidouter blades from' the support tereof and having" aseries of blades mountthereon at one endand extending between if; said two-series oi outerblad'eathe' two se-H ries of blade'sfof fone shaft being oppositely inclined to those'of the other shaftand each l'outer series being disposed to receive Water from the adjacent inner series, substantially.

as described.

'lrivtestirnony whereof, l hare signed-my i name to this Specification, in the 'presence of two subscribing Witnesses.

EDWARD FQ WELCH' Witnesses:

LOUIS H. HA-Rnnvniii,4 H. B. DAVIS.' 

